Number Base

Convert numbers between bases (bin, oct, dec, hex)

About this tool

Convert numbers between the bases most used in programming: binary (2), octal (8), decimal (10) and hexadecimal (16). Pick the source base, type the number and see all four representations at once.

The conversion uses BigInt, so it works even with very large numbers without losing precision — handy for bit masks, colors, memory addresses and low-level values.

How to use

Select the source base (Bin, Oct, Dec or Hex).
Type the number in that base.
Watch the conversions to every base appear instantly.
Use the copy button next to each result.

Frequently asked questions

Does it support negative numbers?

Yes, just include the minus sign before the number.

Is there a size limit?

There's no practical limit: we use BigInt to keep precision for large numbers.

Can I use letters in hexadecimal?

Yes, use a to f (upper or lower case) for the digits 10 to 15.